Hi,
We have a BES server (version 5.0.1.89) as well as a BES router and attachment server which we'll (very) shortly be migrating to another provider.

This means that the servers will not be available for a period of time and will have different IP addresses once they become available.

We have the migration process itself down, but are missing specific BES knowledge of what would be required and what impact it will have during the migration.

We think we have a few good ideas about what impact this will cause and a few on how to complete the migration and ensure services are available but unfortunately we don't have time to learn enough and verify our steps/thoughts.
So I have a few targetted queries for the community to confirm and expand on our thoughts:

Is there a specific shutdown / start up method we should use?

Will this impact our blackberry users while the servers are migrated? (i.e. not contactable)

Our servers will all have new IP addresses assigned but will be resolvable by name. Are any changes required as a result of this? It appears that everything is referenced by name as we would expect...

What ports will need to be open by our new provider once they're migrated?

Have you done a similar migration or have any focused documentation on this type of migration?

I know this is quite an open query, but appreciate any help that you can spare.